The formal paperwork charging Colton Harvey with first-degree murder in the death of his 16-year-old sister, Candace, was filed more than a week after authorities said he showed up at the Franklin County Sheriff's office and told investigators he shot his sister at their family's home near Ozark.

The court filings obtained by The Associated Press also order Harvey not to communicate or be around his parents unless they initiate the conversation. His family didn't return a phone message left at their home in rural western Arkansas on Wednesday.

A judge appointed a public defender to represent Harvey, but no lawyer was listed in the court papers. A public defender responsible for appointing attorneys didn't immediately return a phone message, and prosecutor David Gibbons said he didn't know who would be representing Harvey.

Gibbons has said he planned to charge the boy as an adult "because of the nature of the crime."

Sheriff Anthony Boen said Harvey showed up at his office the morning of Jan. 15 with tears in his eyes and confessed to killing his sister in their home near Ozark, a town of about 3,600 residents roughly 120 miles northwest of Little Rock.

"He just said that he had just shot and killed his sister," Boen said. "... He didn't give a motive."

Investigators believe Harvey killed his sister between 8 a.m., when their parents left to go grocery shopping about 40 miles away, and 9:30 a.m., when he turned himself in at the sheriff's department, Boen said.

Authorities confiscated multiple guns from the family's home and vehicle, and were trying to determine which weapon had been used. The sheriff said the boy and his father were avid hunters.